This invention relates to a reversible refrigeration system which is adapted to deliver optimum performance in either a heating or a cooling mode of operation.
More specifically, this invention relates to a heat pump having control means associated therewith for automatically routing refrigerant to each of the heat exchangers in response to the exchangers' function whereby each exchanger operates efficiently when called upon to serve either as a condenser or as an evaporator.
Most air side heat exchangers employed in refrigeration systems are of the plate fin construction wherein refrigerant is directed through a number of heat transfer zones via flow circuits running through the unit. When the exchanger is used as a condenser, the flow of refrigerant is routed through the circuits so that it passes in series through each zone. On the other hand, when the exchanger is used an an evaporator, the refrigerant is generally routed through each circuit simultaneously to establish a parallel flow through the circuits. As can be seen, the flow geometry associated with a well designed condenser is not compatible with that of a well designed evaporator.
In a heat pump environment, it has been the usual practice to compromise the heat exchanger design in order to permit the exchangers to provide the double duty function required. This, in turn, limited the performance of the entire system.